<!DOCTYPE html>
<html lang="zh-CN">
<head>
<meta charset="UTF-8">
<title>盒子模型</title>
<h1>
    盒子模型示例
</h1>
<style>
  .box {
    width: 200px;
    height: 100px;
    border: 5px solid black;
    padding: 10px;
    margin: 10px;
    background-color: white;
  }
</style>
</head>
<body>
<div class="box"></div>
</body>
</html>